The present invention relates generally to mechanical latching mechanisms and, more particularly, to a uniquely configured push-to-open latch that may be adapted for use as a hidden door latch or a stowable coat hook which are respectively latchable or stowable in response to an external force applied thereto.
In attempts to improve the appearance of interiors such as aircraft interiors as well as to reduce the hazards posed by protrusions such as cabinet handles in such interiors, several prior art latches have been developed wherein the latch is hidden from view. Such latches may be used in applications wherein a door or drawer is latchable to a cabinet or a bin, etc. Prior art latches have included both mechanical and magnetic means to maintain the door in a closed or latched position.
For example, U.S. Letters Pat. No. 4,026,588 issued to Bisbing et al. discloses a push-to-open magnetic catch for a door of a cabinet. As understood, the magnetic catch of Bisbing includes a housing having a magnet mounted therein. The housing is positioned within the cabinet such that the magnet projects forwardly of the cabinet to contact the cabinet door as it closes as well as to maintain the door in the closed position. The door may be opened by initially pushing inwardly on the door which causes the magnet to separate from the door which, in turn, allows a spring-loaded plunger to push the door outwardly when the inward force is removed.
Although the magnetic catch of the Bisbing reference is configured in such a manner as to avoid misalignment of the magnet during subsequent closing of the door, magnetic catches of the type disclosed in Bisbing suffer from several deficiencies that detract from their overall utility. For example, the magnetic catch as disclosed in Bisbing is comprised of bulky components that occupy a relatively large volume of the cabinet interior which may be more preferably utilized for luggage in consideration of the relatively limited storage space that is available in most aircraft interiors. Furthermore, the magnetic catch of Bisbing as well as magnetic latches in general typically can provide only a finite amount of holding force. Such holding force is particularly important in aircraft applications where the aircraft is susceptible to turbulent flight conditions. Under such conditions, magnetic catches may be incapable of withstanding opening forces acting against an inner surface of a cabinet door due to shifting contents or luggage inside the cabinet.
Mechanical latches have also been developed wherein the latch is hidden from view. For example, U.S. Letters Pat. No. 6,669,250 issued to St. Louis and commercially available from St. Louis Designs, Inc. of Austin, Tex. discloses a latch system that may be mounted within a cabinet. The latch system includes a push-to-open latch mounted to the cabinet interior and a catch that is mounted to a door. The push-to-open latch is comprised of a body having an endless groove formed therein. As understood, one end of the lever has a pin which tracks through the groove and is moveable between two stable positions within the endless groove depending on whether the door is to be placed in a closed position or an open position. An opposite end of the lever has a roller which engages the catch in order selectively to move the lever between the closed and open positions by pushing inwardly on the door to alternately move the pin between the two stable positions within the endless groove.
Although the latch system of the St. Louis reference provides a relatively large holding force as compared to similarly sized magnetic catches of the prior art, the latch system of the St. Louis reference may unfortunately result in asymmetric or eccentric loading on individual components which may limit the operating life of the latch system. For example, as understood, the pin is mounted to the lever and is cantilevered off to one side thereof. Such cantilevered mounting may result in the inducement of excessive bending forces within the lever at the pin attachment point should a user attempt to improperly open the door by pulling outwardly, as is more intuitive, that by pushing inwardly as is required to open the door. Even if outward pulling on the door does not initially damage the latch system, the eccentric loads induced on the lever under repeated attempts to open the door may cause the lever to bend so that, eventually, the pin may jam within the groove.
As can be seen, there exists a need in the art for a push-to-open latch that is mountable within a cabinet so as to be hidden from view and which provides a relatively large holding force against pressure exerted against an interior of the door such as may result from shifting luggage within a compartment of an aircraft interior. In addition, there exists a need in the art for a push-to-open latch that is relatively simple in construction in order to reduce fabrication, installation and maintenance costs. Also, there exists a need in the art for a push-to-open latch that is small in size so as to allow for a greater proportion of useful space in confined interiors. Furthermore, there exists a need in the art for a push-to-open latch that is configured to minimize or eliminate the inducement of eccentric loads on components of the push-to-open latch in order to increase the operating life thereof.